Periodontal disease causes oral bone loss and ultimately leads to tooth loss. An estimated 80% of American adults have some form of periodontal disease, and 42% of Americans over the age of 65 (a growing segment of the population) are edentulous. Expenditures for treating these conditions far exceed $6 billion/year. Our long-term goal is to determine the extent to which calcium plus vitamin D improves oral health. The objectives of this clinical trial pilot data grant application are to resolve methodological issues, concerning the radiographic measurement of alveolar bone and to gather preliminary data for sample-size calculations for preparing a phase-Ill, randomized, controlled clinical-trial. This pilot grant application has 3 specific aims: (1) Determine the precision of radiograph-based measurements of alveolar crest height. (2) Determine the differences in alveolar crest heights between patients who are taking calcium (= 1000 mg/day) and vitamin D (= 400 IU/day) supplementation and patients who are taking neither calcium nor vitamin D supplementation. (3) Determine the changes in alveolar crest heights in these 2 groups of patients, by following them prospectively for one year. These specific aims will be achieved through a straightforward observational study, in which periodontal and radiographic data on alveolar bone height will be collected at baseline, at six months, and after one year. Analyses of the baseline data and of the six-month and one-year changes will be performed. The precision of advanced radiographic methods for determining alveolar crest height and alveolar bone mass measurements will also be determined. The possibility of promoting alveolar bone gain or reducing alveolar bone loss with calcium and vitamin D supplementation is significant because it could lead to improved quality of life for older adults with chronic periodontal disease and could result in substantial economic savings to them and to society as a whole. [unreadable] [unreadable] [unreadable]